A communication network may include network elements that route packets through the network. Today, many communications networks are implemented as circuit switched networks, such as Synchronous Optical Networking (SONET) networks, for example. In general, SONET may be described as a standardized multiplexing protocol for transferring multiple digital bit streams over optical fiber using lasers or light-emitting diodes (LEDs). In addition, communications networks may be implemented as packet switched networks, such as Ethernet networks, as an example. In general, a packet-switched network may be a digital communications network that groups all transmitted data, irrespective of content, type, or structure into suitably-sized blocks, called packets. The network over which packets are transmitted is a shared network which routes each packet independently from all others and allocates transmission resources as needed.
Both circuit switched networks and packet switched networks may be organized in ring topologies. A ring network may be a network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node—a ring. Data travels from node to node, with each node along the way handling every packet. Optical networks often employ redundancies to maximize performance and availability. In ring networks, such redundancies may include shared ring protection schemes such as bidirectional line switched ring (BLSR). With BLSR, rather than sending redundant copies of packets from ingress to egress, ring nodes adjacent to a failure may reroute traffic in an opposite direction of the ring in response to a failure. For example, if a failure occurs at a first node intermediate to a second node and a third node in which the first node and second node are “counterclockwise” to the third node, third node may reroute traffic intended for the second node in a “clockwise” direction (e.g., via nodes other than the first node).
Some advantages may exist for packet-based ring networks over circuit-switched ring networks. For example, packet-based rings may provide wide-area multipoint connectivity more economically due to their reduced number of links, while also providing ring protection similar to BLSR. Accordingly, it may be beneficial to reconfigure circuit-switched ring networks to packet-based ring networks. However, doing so using traditional approaches may lead to undesired network downtime.